Meeting The Challenges Of Bioprinting

3D
bioprinting offers opportunities such as testing treatment for diseases using
artificially affected tissues, and through using bioink, it’s much easier to solve
problems on a patient-specific level, promoting simpler operations. Within this
context this article assesses the possibilities that exist for bioprinting, and
looks at a newly introduced technology option that can provide highly reliable
and cost-effective bioprinting options.

With the
growing demand for customized medical devices and pharmaceutical, 3D printing/additive
manufacturing (AM) has begun to iron out a niche for itself in the medical and
life sciences sectors. Throughout industry — but in the life sciences
sector in particular — 3D printing has been truly disruptive, and some
would say revolutionary, and it has promoted the manufacture of personalized
implants and prosthetics, personalized and adjustable dosage forms for drug
delivery, tissue engineering, and disease modeling.

But the
use of AM in life science applications is not necessarily straight-forward. For
example, the physiochemical and biopharmaceutical characteristics of active
pharmaceutical ingredients (APIs) in drug formulations are extremely varied,
and need to be considered alongside any proposed AM drug delivery solution.
However, the over-riding demand for patient-centric drug and medical product
development means that AM’s future is secured in the life sciences sector.

AM is now
an established technology in the manufacture of models (phantoms) for surgical
planning and training, implants and prostheses, patient specific anti-microbial
wound dressings, and some novel forms of drug delivery, but a relatively less
advanced area, and one in which FELIXprinters is working actively is in the
field of bioprinting and so called “organs-on-chip”.

THE BIOPRINTING
MARKET

The global 3D bioprinting market
— currently valued at $965 million — is expected to grow at a CAGR of nearly
20% up to the mid 2020s, driven by increased healthcare demands, but also to
overcome the supply bottlenecks and ethical issues associated with organ
donation and tissue repair. Bioprinting also caters for the increased demand
for customized patient-specific healthcare solutions, a trend that is only
likely to accelerate moving forward.

The key
stimulus behind AM driven bioprinting is to find a solution for organ / tissue
rejection, and the requirement for lifelong immunosuppressant-based therapies.
The area of regenerative medicine is constantly on the look out for mechanisms
that allow for the fabrication of multi-layer soft biological materials such as
living cells, and in this extremely exacting area of research, AM is finding a
foothold.

Wilgo
Feliksdal, Co-Founder of FELIXprinters explains, “To date, AM has been mainly
used for the preparation of tissue construct such as blood vessels, liver,
kidneys, heart tissue, cartilage, and bone. But all developments in this area
of the use of AM requires a focus on the long-term viability of the “printed”
cells, the control of cell proliferation so as to provide sufficient amount of
functional and supporting cells and tissue homeostasis, and the requirement for
tissues used in 3D printing to be able to survive pressure and shear stress during
the 3D printing process, as well as contact with potentially harmful compounds.”

A NEW
BIOPRINTING OPTION

With this
in mind, FELIXprinters has recently launched its BIOprinter which has been developed on the chassis of the
established FELIXprinters’ product line which includes the Pro and Tec series
and the Pro L & XL machines. This means that at its heart is the tried and
tested technology that has already been serving industry successfully for
years.

The BIOprinter is characterized
by key features that are specifically designed for medical, scientific, and
research applications, including syringe cooling, print bed cooling and
heating, a dual head system, easy syringe positioning (ergonomic access to the
machine supports researchers in their work), and automatic bed levelling.

Guillaume Feliksdal, Co-Founder
says, “The BIOprinter has been designed to be the ultimate bio research
instrument but in a cost-effective package. It has been developed alongside the
brightest minds in the bioprinting sector, and we partnered with training4crm
and the Technical University of Denmark (DTU), and received funding from the
European Union Horizon 2020 Programme to develop the BIOprinter. Uniquely, the
BIOprinter combines dual sterilizable printheads which have a modular design
for easy changeovers, and separate heads are available to print different
bioinks at the same time. This integrates different material properties into a
single scaffold structure.”

FELIXprinters
has worked closely with the Technical University of Denmark (DTU) on
bioprinting applications of 3D printing. Heading the research was Hakan Gürbüz,
who explains the foundation of the work he is undertaking.

“The aim
of the BIOprinter that we have developed with FELIXprinters is to allow the printing
of scalable and perfusable hybrid scaffold structures, incorporating in the
same structure at least two different material properties. For this purpose, we
developed a hybrid 3D printing platform that enables the printing of 3D
scaffolds with dual material properties (e.g. mechanical [soft/medium/hard],
conductive or biological) and perfusable micro-channel networks, enabling the
continuous supply of oxygen, nutrients, and necessary factors to cells growing
and differentiating throughout the scaffold.”

3D
printing has many advantages over conventional approaches to building
scaffolds, not least its ability to position the cells precisely. Currently,
there are three different classes of bioprinters that are used for deposition
and patterning of biological materials including inkjet, micro-extrusion, and
laser-assisted printing options. Each of these bioprinters has unique methods
of depositing 3D cell structures with good resolution and viability. The FELIX
BIOprinter is a micro-extrusion bioprinter, which makes it very simple to use.

Wilgo
Feliksdal explains how micro-extrusion printers work. “Micro-extrusion
bioprinters usually consist of a temperature-controlled biomaterial dispensing
system, a stage capable of moving in the x, y, and z directions, light
illuminated deposition area for photo-initiator activation, and a video camera for
x-y-z command. Unlike other bioprinters, the micro-extrusion bioprinter
generates a continuous string of bioink rather than many droplets of bioink by
applying pressure — either pneumatically or mechanically — to force the
bioink from a syringe.”

“These
strings are deposited in 2-dimensional layers (as directed by the CAD-CAM
software), and served as the base for the subsequent layers while the stage is
moved up the z-axis, resulting in the formation of a 3D structure. Micro-extrusion
bioprinters are compatible with a wider selection of bioink including high
viscosity materials such as hydrogels, biocompatible copolymers, and cell
spheroids.”

Effectively, the BIOprinter
consists of an adaptable and flexible ecosystem to ensure that it can meet a
wide range of researchers’ needs without generating unnecessary costs. One
major advantage is the source control system which enables the user to use
standard slicing software and make changes themselves if needed. Also, syringes
are not restricted to expensive brand-specific or in-house produced products
that essentially drive up operating costs. The machine instead has been
designed to use a standard 5ml syringe, and standardized petri dishes and
culture plates, so there are no limitations on auxiliary parts and materials.

The FELIX BIOprinter is
appropriate for all types of bioprinting research, and is equipped with strong
motors that can extrude a range of different viscosity of materials. In
addition, the BIOprinter has been designed to be easily upgradeable, which
means that the lifecycle of the machine can be extended without compromising
quality, reliability, and productivity.

The platform has automatic bed
levelling through the use of a unique probing system which results in a completely
accurate first layer, which means a high quality end result. It also retracts
with a highly precise motor for better dosage or materials and more accurate
material flow versus alternative air pressure systems.

SUMMARY

Given its interdisciplinary nature, 3D bioprinting is accelerating at an ever-increasing rate. It’s exciting times, but we need to be careful to temper our expectations of this technology with the realities. The human body is incredibly complex, and trying to replicate the many things that it does is difficult. Those working in the field are making advances every day, in both the technology and in their understanding of how it can be used and improved. There is no doubt that the future of medicine will be very different with bioprinting involved, and the FELIX BIOprinter is perfectly positioned to cater for the spike in demand in the coming years as research in this area continues to expand.

FELIXprinters is headquartered in
IJsselstein, the Netherlands, and was established in 2010, since when it has
established itself as one of only a very few 3D printing technology suppliers
that has an understanding of the requirements of the market for 3D printers.
The company provides top-end, robust, reliable, and competitively priced 3D
printing solutions for industry users. Beyond the optimisation of its
industrial range of printers, however, FELIXprinters has extensive engineering
and R&D capabilities, which it is able to utilize to provide specific
services in the development of tailor-made, customised 3D printing platforms —
working in partnership to produce new and innovative solutions.